Demonstration program for a simple Human class

Human.java

/**
 * Represents a single human being
 * 
 * This class is basically only a storage
 * there is no direct logic in this class
 *
 */
/**
 * @author ATGEMET
 *
 */
public class Human {

	/**
	 * Member variable for the Name of the Human
	 */
	private String name;

	/**
	 * Default constructor.
	 * 
	 * Generates a new Human with an empty name (indicating that the Human is
	 * not named yet.)
	 */
	public Human() {
		name = "";
	}

	/**
	 * Generates a new Human with the given name
	 * 
	 * @param name the name for the new Human
	 */
	public Human(String name) {
		this.name = name;
	}

	/**
	 * Gives an existing Human a new name
	 * (think baptizing, marriage)
	 * 
	 * @param name
	 */
	public void setName(String name) {
		this.name = name;
	}

	/**
	 * Returns the name of the Human
	 * 
	 * @return the name of the Human
	 */
	public String getName() {
		return name;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#toString()
	 * 
	 * This method is used when you want to print the
	 * information about a single Human
	 * 
	 */
	@Override
	public String toString() {
		return "My name is: " + name + ".";
	}
}

Humans.java

import java.util.Random;

/**
 * Stores several generated Human instances in an array
 * 
 *
 */
public class Humans {

	/**
	 * The internal storage for the Human instances
	 */
	private Human[] people;

	/**
	 * A list of valid human names from which one will be picked
	 */
	private static final String[] HUMAN_NAMES = { "Frank", "John", "Joe",
			"Izobel", "June", "Camilla" };

	/**
	 * Just a random number generator - nothing special
	 */
	private static Random generator = new Random();

	/**
	 * The default constructor for the Humans class
	 * 
	 * In this constructor, a random number is generated which then is used to
	 * dimension an array of Human instances that consecutively will be filled
	 * with Human instances who are given random names.
	 */
	public Humans() {

		// generate a random amount between 1 and 3
		int numberOfHumans = Humans.generator.nextInt(3) + 1;

		// dimension the storage for the new humans
		people = new Human[numberOfHumans];

		// From here on, the actual Human instances are created
		for (int i = 0; i < people.length; i++) {

			// the following snippet explains the uncommented line in detailed
			// steps:
			// You can remove the block comment too activate the code

			/*
			 * int randomNameIndex =
			 * Humans.generator(nextInt(Humans.HUMAN_NAMES.length); // generate
			 * a new random index inside the range of the HUMAN_NAMES array
			 * String randomName = Humans.HUMAN_NAMES[randomNameIndex]; // get a
			 * random name from the Array people[i] = new Human();
			 * people[i].setName(randomName);
			 */

			// the code in the line below condenses all four lines above into a
			// single line
			// When testing, make sure that either the above four lines, or the
			// line below are active, not both!
			people[i] = new Human(
					Humans.HUMAN_NAMES[generator
							.nextInt(Humans.HUMAN_NAMES.length)]);

		}
	}

	/**
	 * @return the array of Human instances
	 */
	public Human[] getpeople() {
		return people;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#toString()
	 * 
	 * This method prints a nice list of all the Human instances stored in the
	 * class
	 */
	@Override
	public String toString() {

		// since it is bad to join String values with "+", I'll use a
		// StringBuilder
		// here
		StringBuilder sb = new StringBuilder();

		// append some header information
		sb.append("I have " + people.length
				+ (people.length == 1 ? " person" : " people") + " in my list.");
		sb.append("Let me introduce you to them:\n\n");

		// go through the array of people and let every member
		// introduce themselves.
		for (int i = 0; i < people.length; i++) {
			sb.append("#" + i + " " + people[i] + "\n");
		}
		
		
		// return the completed String
		return sb.toString();
	}

}

HumanTester.java

/**
 * This class only acts as a tester for the Humans class
 * 
 * Basically, the main method here could be integrated in
 * the Humans class - still it is not advisable to do so
 * because if the class is to be reused, the main method 
 * could get in the way
 *
 */
public class HumanTester {

	
	public static void main(String[] args) {
	
		// create a new instance of the Humans
		Humans people = new Humans();
		
		// print out its contents
		System.out.println(people);
	}
}